The tremendous growth in demand for wireless services has fostered an environment where multiple service providers may coexist to provide similar coverage and services in a given geographical area. This is particularly the trend in the United States where as many as two, three or more wireless operators may compete in a given metropolitan trading area (MTA). In this type of competitive environment, mobile subscribers are likely to seek out the lowest cost operator among competing service providers. A comparable situation currently exists among long distance carriers in the United States where customers, while receiving essentially the same level of service, can compare prices for a typical long distance call as a factor in choosing one carrier over another. Similarly, wireless operators will have an incentive to compete for mobile subscribers and to advertise their price and services in an effort to attract customers.
There have been a number of proposals put forth in the past that specify systems to permit subscribers to obtain tariff information charged by various service providers. FIG. 1 illustrates a prior art technique in which tariff information can be obtained by an individual subscriber for the purpose of choosing the cheapest service provider. For example, a mobile terminal 10 is located in an area where it has potential access to three service providers, each of which providing substantially similar service and coverage. The three providers may be operating in accordance with the same standard, thus only requiring a single standard phone, or they may be operating in accordance with different wireless standards. A multi-standard mobile terminal is required to access these systems operating on different standards.
In order to access tariff information, mobile terminal 10 proceeds to register to gain access with a service provider that is within his capability, such as provider A for example. Once access has been established, mobile terminal 10 sends a request to provider A for tariff information. Moreover, the request inquires about tariff information on competitors such as providers B and C. Upon receiving the request, provider A relays the request via the public switched telephone network (PSTN) 12 to an attached centralized server 14. The network providers are in communication with server 14 via the PTSN such that server 14 is able to maintain current tariff information on all participating systems through frequent updates. The requested tariff information is then relayed back through provider A to mobile terminal 10 for analysis. The mobile then has the option of establishing a connection with any of the other service providers B or C based on price, priority or some other predetermined parameter.
One major disadvantage with the aforementioned approach is that implementation is complex and requires substantial changes in current network systems for implementation. By way of example, significant changes in software and control messages must be incorporated to accommodate the central tariff server thereby making backward compatibility with existing networks difficult. Furthermore, the approach requires the subscriber to undergo a registration process in order to gain access to a service provider thereby accruing the costs associated with registration for tariff investigation. Additionally the approach potentially requires the subscriber to terminate his current service and re-register with a another provider if it is determined that this is preferable. Other considerations may include cost and reliability. For example, server 14 may be maintained by a third party thereby increasing the cost. Furthermore, the tariff information stored on the server is only indirectly accessed by the mobile terminal 10, thus the usefulness to the subscriber depends wholly on timely updates and server reliability.
In view of the foregoing, it is an objective of the present invention to provide a method for permitting access to tariff information without requiring the subscriber to first register with a service provider. A further objective is to provide a cost efficient, relatively less complex system that is more backward compatible with existing systems and standards.